The Oshika Peninsula also pronounced "Ojika" is a peninsula which projects southeast into the Pacific Ocean from the coast of Miyagi Prefecture in northeast Honshu, the main island of Japan.

Miyagi Prefecture is a prefecture of Japan located in the Tōhoku region of Honshu. Miyagi Prefecture has a population of 2,265,724 and has a geographic area of 7,282 km2 (2,812 sq mi). Miyagi Prefecture borders Iwate Prefecture to the north, Akita Prefecture to the northwest, Yamagata Prefecture to the west, and Fukushima Prefecture to the south.